Heretofore, as for drink containers, can-type drink containers filled with alcohol such as beer, soft drinks such as sports drink, and beverages such as coffee have been sold on the market. Typically, a user who bought such a drink opens a drinking mouth provided on the drink container by hand and drinks the liquid flowing out from the opened drinking mouth by putting his mouth to the vicinity of said drinking mouth.
Such a can-type container is inconvenient because its drinking mouth cannot be closed again if it is opened once, and it may be not clean for the user to put his mouth directly to the drinking mouth. Therefore, a method to provide removable seal on the upper surface of the drink container has been proposed (Japan Patent Laid-open No. H9-48449 Bulletin).
Such a drink container having a seal around its drinking mouth has an advantage because even if it is opened once, the drinking mouth can be resealed, resulting in effectively preventing the spill of liquid contained in the container from the drinking mouth and the uncleanness around the drinking mouth to which the user's mouth directly touches. On the other hand, there is a possibility of occurrence of the secondary accident due to illegally using a used product which was opened once and then returned to the original condition (hereinafter referred to as tampering) so as to look like an unused new product.
Furthermore, providing a similar seal which can be reattached after being peeled off, on the upper part of the can-type container is convenient for users but there is a possibility of the occurrence of the secondary accident.